#include<stdio.h>
int main(){
    char arr[30];
    gets(arr);
    int count=0;
    for(int i=0;arr[i]!='\0';i++){
        if(arr[i]>='0' &&arr[i]<='9'||arr[i]>='a'&&arr[i]<='z'||arr[i]>='A'&&arr[i]<='Z'){
            count++;
        }
    }  
    printf("%d",count);                
    return 0;
}